Cottage Grove Dam and Reservoir is located at river mile 29 of the Coast Fork of the Willamette River, about five miles south of Cottage Grove, OR.

Water Temperature:In a normal year, the surface water temperature (top 12-18 inches) should be in the 72-75F range at Cottage Grove Lake. We will announce the water temperature on our Facebook page as the race gets closer.

For more information about the lake, check out the Army Corps Cottage Grove Lake website.Wet suits:Athletes at the Tri at the Grove have the option to wear a wet suit. Wet suits are not mandatory. In the event of exceptionally warm water conditions, USAT regulations will be followed:USAT Competitive Rulebook, Article IV4.4 Wet suits. Each age group participant shall be permitted to wear a wet suit without penalty in any event sanctioned by USA Triathlon up to and including a water temperature of 78 degrees Fahrenheit. When the water temperature is greater than 78 degrees, but less than 84 degrees Fahrenheit, age group participants may wear a wet suit at their own discretion, provided however that participants who wear a wet suit within this temperature range shall not be eligible for prizes or awards. Age group participants shall not wear wet suits in water temperatures equal to or greater than 84 degrees Fahrenheit.FAQ: Do I need a wet suit?No, wet suits are optional at this race. The water temperature at Cottage Grove Lake is a comfortable 72-75 degrees Fahrenheit.